#if defined(R4000) // TITLE("Interval and Profile Clock Interrupts") //++ // // Copyright (c) 1991 Microsoft Corporation // // Module Name: // // x4clock.s // // Abstract: // // This module implements the code necessary to field and process the // interval and profile clock interrupts on a MIPS R4000 system. // // Author: // // David N. Cutler (davec) 26-Apr-1991 // // Environment: // // Kernel mode only. // // Revision History: // //-- #include "halmips.h" #include "jazzdef.h" SBTTL("System Clock Interrupt") //++ // // Routine Description: // // This routine is entered as the result of an interrupt generated by // the interval timer. Its function is to acknowledge the interrupt and // transfer control to the standard system routine to update the system // time and the execution time of the current thread and process. // // Arguments: // // s8 - Supplies a pointer to a trap frame. // // Return Value: // // None. // //-- .struct 0 CiArgs: .space 4 * 4 // saved arguments .space 3 * 4 // fill CiRa: .space 4 // saved return address CiFrameLength: // NESTED_ENTRY(HalpClockInterrupt, CiFrameLength, zero) subu sp,sp,CiFrameLength // allocate stack frame sw ra,CiRa(sp) // save return address PROLOGUE_END .set noreorder lw t0,DMA_VIRTUAL_BASE + 0x230 // acknowledge timer interrupt .set reorder move a0,s8 // set address of trap frame lw a1,HalpCurrentTimeIncrement // set current time increment jal KeUpdateSystemTime // update system time // // At each clock interrupt the next time increment is moved to the current // time increment to "pipeline" the update of the current increment at the // correct time. If the next interval count is nonzero, then the new time // increment is moved to the next time increment and the next interval count // register is loaded with the specified interval count minus one (i.e., ms). // lw t0,KdDebuggerEnabled // get address of debugger enable lw t1,HalpNextIntervalCount // get next interval count lw t2,HalpNextTimeIncrement // get the next increment value lbu t0,0(t0) // get debugger enable flag lw t3,HalpNewTimeIncrement // get new new time increment value lw ra,CiRa(sp) // restore return address or t4,t1,t0 // set interval count or debugger? sw t2,HalpCurrentTimeIncrement // set current increment value bne zero,t4,10f // if ne, interval change or debugger addu sp,sp,CiFrameLength // deallocate stack frame j ra // return // // The interval count must be changed or the debugger is enabled. // 10: sw zero,HalpNextIntervalCount // clear next interval count beq zero,t1,20f // if eq, not interval count change subu t1,t1,1 // compute millisecond interval count sw t1,DMA_VIRTUAL_BASE + 0x228 // set next interval count sw t3,HalpNextTimeIncrement // set next time increment value 20: beq zero,t0,30f // if eq, debugger not enabled jal KdPollBreakIn // check if breakin is requested beq zero,v0,30f // if eq, no breakin requested li a0,DBG_STATUS_CONTROL_C // break in and send jal DbgBreakPointWithStatus // status to debugger 30: lw ra,CiRa(sp) // restore return address addu sp,sp,CiFrameLength // deallocate stack frame j ra // return .end HalpClockInterrupt SBTTL("Profile Clock Interrupt") //++ // // Routine Description: // // This routine is entered as the result of an interrupt generated by the // profile clock. Its function is to acknowledge the profile interrupt, // compute the next compare value, update the performance counter, and // transfer control to the standard system routine to process any active // profiles. // // Arguments: // // s8 - Supplies a pointer to a trap frame. // // Return Value: // // None. // //-- LEAF_ENTRY(HalpProfileInterrupt) .set noreorder .set noat mfc0 t1,count // get current count value mfc0 t0,compare // get current comparison value addu t1,t1,8 // factor in lost cycles subu t1,t1,t0 // compute initial count value mtc0 t0,compare // dismiss interrupt mtc0 t1,count // set new count register value .set at .set reorder la t1,HalpPerformanceCounter // get performance counter address lw t2,LiLowPart(t1) // get low part of performance count lw t3,LiHighPart(t1) // get high part of performance count addu t2,t2,t0 // update low part of performance count sw t2,LiLowPart(t1) // store low part of performance count sltu t4,t2,t0 // generate carry into high part addu t3,t3,t4 // update high part of performance count sw t3,LiHighPart(t1) // store high part of performance count move a0,s8 // set address of trap frame j KeProfileInterrupt // process profile entries .end HalpProfileInterrupt SBTTL("Read Count Register") //++ // // ULONG // HalpReadCountRegister ( // VOID // ); // // Routine Description: // // This routine reads the current value of the count register and // returns the value. // // Arguments: // // None. // // Return Value: // // Current value of the count register. // //-- LEAF_ENTRY(HalpReadCountRegister) .set noreorder .set noat mfc0 v0,count // get count register value .set at .set reorder j ra // return .end HalpReadCountRegister SBTTL("Write Compare Register And Clear") //++ // // ULONG // HalpWriteCompareRegisterAndClear ( // IN ULONG Value // ); // // Routine Description: // // This routine reads the current value of the count register, writes // the value of the compare register, clears the count register, and // returns the previous value of the count register. // // Arguments: // // Value - Supplies the value written to the compare register. // // Return Value: // // Previous value of the count register. // //-- LEAF_ENTRY(HalpWriteCompareRegisterAndClear) .set noreorder .set noat mfc0 v0,count // get count register value mtc0 a0,compare // set compare register value li t0,7 // set lost cycle count mtc0 t0,count // set count register to zero .set at .set reorder j ra // return .end HalpWriteCompareRegisterAndClear #endif